Pro-Russia gunmen overran three eastern Ukrainian military bases on Wednesday, making off with weapons and armored vehicles after ill-equipped government forces ran out of ammunition and fled, Kiev officials and media reported.

The setbacks in the Ukrainian government's campaign to retake key facilities seized by the militants two months ago prompted acting President Oleksandr Turchynov to appeal to the nation's security agencies to consider imposing martial law.

CaptionCrisis in Ukraine

Alexander Khudoteply / AFP/Getty Images

A lone pedestrian passes through a once-bustling area of Donetsk on Nov. 13. Commercial buildings, government offices and thousands of homes have been destroyed in the city in seven months of fighting between separatists and Ukrainian troops.

A lone pedestrian passes through a once-bustling area of Donetsk on Nov. 13. Commercial buildings, government offices and thousands of homes have been destroyed in the city in seven months of fighting between separatists and Ukrainian troops. (Alexander Khudoteply / AFP/Getty Images)

An activist from the Ukrainian Internet Party, dressed as Darth Vader from the "Star Wars" movies, shows his passport at a polling station in Kiev during parliamentary elections on Oct. 26.

An activist from the Ukrainian Internet Party, dressed as Darth Vader from the "Star Wars" movies, shows his passport at a polling station in Kiev during parliamentary elections on Oct. 26. (Sergei Gapon / AFP/Getty Images)

Fighting between the Russia-allied separatists and Ukrainians trying to thwart further territorial losses has intensified in the days leading up to President-elect Petro Poroshenko's inauguration on Saturday. The initial response among security officials in Kiev to Turchynov's call for a martial law debate was that the step would be considered only after Poroshenko has been sworn in as head of state.

Each side claimed to have inflicted massive losses on the other as fighting around the front-line town of Slovyansk continued for a second day Wednesday, as did a siege of a Ukrainian border guards base and National Guard compound near Luhansk. International and domestic media reported both bases overrun by militants early Wednesday, and the Associated Press said a third military unit was ousted from its compound in Sverdlovsk, near the Russian border.

At least 300 separatists were killed in the two days of fighting around the border guards base in Mirny, on the outskirts of Luhansk, Vladyslav Selezniov, spokesman for the Ukrainian military's "anti-terrorist operation," said via telephone hookup with journalists in Kiev from his position near Donetsk.

Separatists, whom Kiev authorities accuse of being armed and instigated by Russian President Vladimir Putin's government, seized regional government headquarters in Donetsk and Luhansk regions two months ago and proclaimed the territory they hold independent from Kiev's rule after staging dubious referendums on May 11.

The casualty toll reported by Selezniov, who said two Ukrainian soldiers were killed, could not be independently confirmed amid the exchanges of gunfire that have kept journalists, and noncombatant officers such as Selezniov, away from the scene of the fighting in the wooded surroundings of Slovyansk, a town of 125,000.

The self-proclaimed mayor of Slovyansk, Vyacheslav Ponomaryov, told Russia's Interfax news agency in the besieged town that his forces had suffered 10 fatalities and shot down a Ukrainian fighter jet and a helicopter. He said they also seized "several tanks and one armored personnel carrier" from the government forces in the latest fighting. Like the Kiev government's accounts of the fighting, the rebel leader's claims couldn't be verified.

Russian state television reported that more than 9,000 refugees from eastern Ukraine have crossed into Russia to escape the fighting, and that 2,000 of them were moved to Crimea, the Ukrainian Black Sea peninsula seized by Russian troops in February and annexed by the Kremlin in March. The rest have taken refuge in the Rostov-on-Don region, prompting local officials to declare a state of emergency, Russia-24 TV said.

Reports from both Kiev and Russia painted a bleak picture of the state of the Ukrainian border guards trying to fend off pro-Russia gunmen for a second day at the base in Mirny. After the border guards and National Guard troops backing them at the base ran out of ammunition, they retreated from the compound, the National Guard said in a statement.

Separatist gunmen who entered the base after its defenders fled were seen hauling away crates of munitions in vehicles also looted from the base, the Associated Press reported from the scene.

Poroshenko vowed the day after his May 25 landslide victory in Ukraine's presidential election to immediately shore up the beleaguered armed forces so they can bring an end to the separatist violence in a matter of days.

President Obama promised in a meeting with Poroshenko in Warsaw on Wednesday to provide $5 million in nonlethal aid to Ukraine's military to equip soldiers with body armor and secure communications.

Ukraine's interim leaders blame former President Viktor Yanukovich for neglecting the military during his four years in office. The Kremlin-allied leader was driven out of Kiev in February by a three-month rebellion against his decision to scrap a trade and political alliance with the European Union, an association agreement that Poroshenko has said he will sign as soon as he becomes president.

Times staff writer Sergei L. Loiko in Moscow contributed to this report.

President Obama’s pledge to defend allies in the former communist states of Eastern Europe and to seek $1 billion from Congress to bolster regional defenses might be Russian President Vladimir Putin’s nightmare come to life.

Bryan Santana, the man accused of stabbing his roommate and defiling her corpse, tried to punch a corrections officer, soiled himself and smeared excrement on the wall of a holding cell before his murder trial was due to begin on Tuesday.